This invention relates generally to power supplies. More specifically, the present invention relates to switching power supplies used in or with computer systems. Also, the present invention relates to switching power supplies used in conjunction with battery back-up systems for operation during the failure of power being supplied to a computer system.
Computers as well as many other digital electronic devices require high quality electric power for their proper operation. For these devices ordinary line power (i.e., power from wall sockets found in many homes and buildings) contains constant voltage fluctuations which are intolerable.
Therefore it is necessary to upgrade the quality of the line power. This is accomplished by rectification, filtering and regulation. Rectification changes the input (line) voltage from an alternating one (AC) to a pulsating direct current (DC) voltage. Filtering converts the pulsating DC voltage to a smooth DC voltage. Finally, regulation steadies the output voltage connected to the load at the desired level.
Many computer systems contain power supplies for delivering multiple voltage outputs which are manufactured separately from the system as a whole. Changing the power supply characteristics of such a system often involves replacement of the entire power supply, is complicated and is often time-consuming.
Additionally, prior art power supplies often contain potentiometers to set output voltages. While this is a feasible approach, there are many problems associated therewith. First, potentiometers are generally one of the least reliable components associated with power systems, often falling into disrepair. Second, because potentiometers are usually manually adjusted, human errors can contribute to improper operation of the system. Finally, the adjusting mechanisms (e.g., knobs) must be made accessible, which can sometimes complicate the package design.
Finally, prior art power supplies for computer systems are generally inefficiently cooled.